It is known that a mere sunlight reflector mounted on a satellite is not able to light up such a surface area of the Earth, unless using a reflector with a very large area, then supposing very high mass and inertia with all the (implementation, cost, positioning, etc.) problems resulting therefrom. As an illustration, should a surface be lit up of approximately one hundred square kilometers on the Earth, a reflector should undoubtfully be provided having its surface area of the order of several thousands of square meters if a total power of several megawatts was to be available. Now, a reflector (a mirror) with such a surface area would not only be difficult to achieve and to put in orbit, but would have such inertia that a possible re-pointing would require a powerful propelling system and would be quite time consuming. Thus, it would be difficult to regularly carry out repointings, so that it would be hardly conceivable to frequently modify the area to be lit up.
Furthermore, the document U.S. Pat. No. 5,019,768 discloses a system for transmitting micro-waves from the Moon to the Earth, using a micro-wave reflector being placed in orbit around the Earth and sending back to the Earth a radiation received from the Moon. Such a reflecting satellite is not able to light up a large surface area of the Earth.